We have developed a sensitive nephrin RT-QPCR (Unep) assay to detect podocyte products in urine. This assay uses a novel AmpliSensor RT-QPCR technique superior to conventional RT-QPCR methodologies. The hypothesis that underlies this approach is that the progression of glomerular diseases (such as diabetes, hypertension, FSGS and immune glomerulopathies) is associated with podocyte loss from glomeruli. If this hypothesis is correct then the measurement of urine podocyte loss via a sensitive and specific assay may provide a valuable adjunct to current clinical strategies for measuring progression of renal diseases (measurement of GFR, protein excretion and renal biopsy which as currently performed does not measure podocyte loss directly). In contrast, the nephrin RT-QPCR (Unep) technique sensitively and specifically detects a podocyte productin in urine (nephrin) regardless of the status of albuminuria or renal function. Thus the test is designed to measure the status of ongoing podocyte injury and its response to therapeutic intervention. To further validate and assess the potential urility of the assay we will perform the following studies: Aim 1. Using epithelial cells that are stably transfected with human, rat and mouse nephrin (provided by Dr. Holzman) we will recreate simulated and real urine containing these cells to determine stability and optimal conditions for the Unep assay in man and rodents. Aim 2. We will use the rat Unep assay in a well-established a model of progressive glomerutosclerosis (partial nephrectomy model) to determine whether the rate of progression is reflected by quantitation of Unep, and whether treatment of rats with an ACE inhibitor to slow the rate of progression is reflected by quantitatively less Unep in urine. Aim 3. We will use the optimised human Unep asssay expressed as Unep copies per mg creatinine to measure Unep in urine samples provided by Dr. Hildebrandt from humans with FSGS in relation to genetically identified forms of glomeruloscierosis. The development of an assay that can non-invasively quantitate the rate of podocyte toss into the urine and thereby sensitively and specifically measure the rate of ongoing podocyte injury and the effect of treatment strategies would be a valuable adjunct to current clinical practice.